Electric space heater

ABSTRACT

An electric heater of the space heating type. The heater includes a housing containing an open-faced reflector. The reflector has within it a heating element suspended in front of a reflective surface between spaced opposing insulator members that pass through forwardly extending walls of the reflector. Some of the insulator members that pass through the reflector walls also pass through individual leaf springs located outside the reflector, which springs are secured within the heater in such a manner that the heating element can be positioned in close proximity to the reflective surface for maximum heat output.

United States Patent 269,760 12/1882 Weston William A. OmohundroWestport, Conn.

Dec. 29, 1969 Oct. 5, 1971 General Electric Company inventor Appl. No.Filed Patented Assignee ELECTRIC SPACE HEATER 10 Claims, 6 Drawing Figs.

US. Cl 219/377, 219/347, 219/355, 219/532,'219/542, 338/316 Int. Cl F24h3/04, l-lOlc 1/02, HOSb 3/32 Field of Search ..219/347-349, 355, 357,377, 532, 536, 537,542,

References Cited UNITED STATES PATENTS 3,019,324 1/1962 Sohn 2l9/355XPrimary Examiner-11.1". Staubly AttorneysLawrence R. Kempton, Leonard J.Platt,

Frederick P. Weidner, Frank L. Neuhauser, Oscar B. Waddell and Joseph B.Forman ABSTRACT: An electric heater of the space heating type. Theheater includes a housing containing an open-faced reflector. Thereflector has within it a heating element suspended in front of areflective surface between spaced opposing insulator members that passthrough forwardly extending walls of the reflector. Some of theinsulator members that pass through the reflector walls also passthrough individual leaf springs located outside the reflector, whichsprings are secured within the heater in such a manner that the heatingelement can be positioned in close proximity to the reflective surfacefor maximum heat output.

sum 1 OF 3 Inventor-- Wilham A. Omohundvo fittorngy PATENTEUOBT 519m3,610,882

sum 3 0r 3 I Inventor Wnuam AOmohundvo Attomgg ELECTRIC SPACE HEATERBACKGROUND OF THE INVENTION This invention relates to electric heaters,and more particularly to portable electric space heaters utilizing asuspended electrical resistance heating element.

Electric space heaters usually have a housing which has a major portionof its front open for receiving therebehind an open-faced reflector.Within the reflector is an electrical resistance element for supplyingheat energy. These electric space heaters are usually small in size anddesigned to be readily and easily portable. In some heaters, the heatingelement is a helically wound resistance wire supported at shortintervals across the reflector. Helical heating element wire is oftenwound around a ceramic rod that extends from one side of the reflectorto the other. Many heaters use a metal ribbontype heating element inwhich the heating element is suspended by means of insulators so that ittraverses the reflector from one side to the other within the reflectorin a serpentine pattern. The expansion of the heating element uponenergization or heating and contraction upon deenergization or coolingcan detrimentally affect the life of the suspended heating element aswell as detract from the appearance of the heater due to the sagging ofthe heating element when it is energized to supply heat. Moreover, themovement of the heating element caused by the expansion and contractionmakes satisfactory terminal connections difficult and often causes themto fail prematurely. This invention has particular application toelectric heaters utilizing a heating element arrangement wherein theheating element is suspended within the reflector and supported only atthe ends of the reflective surface such as is common practice in thecase of ribbon-type heating elements. Various systems have been used inprior electric heater devices to compensate for the expansion andcontraction of the heating element to retain the heating element taut atall times. Some prior electric heater devices use tensioned end walls ofthe reflector to keep the attached ribbon taut while others use variousspring arrangements.

The desirability of keeping heating elements taut has been wellrecognized for years, however, a particular arrangement for achievingthis result should contribute to the overall economy and optimumperformance of the heater into which it is incorporated. Obtaining suchan arrangement is made quite difficult by the relatively small size ofthese electric heaters.

By my invention, there is provided an improved electric heater utilizinga suspended heating element, particularly of the ribbon type thatincorporates an arrangement for maintaining the heating element taut atall times and which cooperates with other features of the heater toprovide a heater that is relatively small in bulk and size, neat inappearance and highly effective for space heating purposes.

SUMMARY OF THE INVENTION In accordance with this invention, there isprovided an electric heater that includes a reflector located behind anopening in the front of the heater. The reflector has a reflectivesurface and at least two walls projecting forwardly from opposite endsof the reflective surface. The reflector has within it a heating elementsuspended in a serpentine pattern to provide continuous runs of aheating element between spaced opposing insulators that pass throughapertures in two of the forwardly projecting walls of the reflector. Theheating element is electrically connected through terminals to a powersource and all of said terminal connections are located. on one of theforwardly projecting walls of the reflector. In the opposite forwardlyprojecting reflector wall each of the insulators which receive a run ofthe heating element connected to a terminal are moveable relative tosaid reflector wall and are cooperatively associated with leaf springsto maintain the heating element suspended thereon taut at all times. Theleaf springs are located outside the reflector and they are arrangedparallel with respect to each other. Each leaf spring is positionedwithin the heater by having one leg secured at a point forward of thereflective surface and the other leg secured at a point rearward of thereflective surface. By this arrangement relatively long leaf springsthat afford maximum displacement with minimum tension force throughoutthe extent of spring displacement may be utilized in order to keep theruns of heating element suspended on each of the moveable insulatorstaut at all times and the suspended heating element may be positioned inclose proximity to the rear wall reflective surface of the reflector formaximum heat output.

It is an object of this invention to provide an improved electric heaterutilizing a suspended heating element.

It is also an object of this invention to provide an electric heaterwith a spring arrangement for maintaining the heating element taut atall times, which arrangement affords maximum spring displacement withminimum tension force throughout the extent of spring displacement.

It is another object of this invention to provide an electric heaterwith an open front, a reflective surface therebehind and a springarrangement for maintaining a heating element suspended across the openfront of the heater taut at all times with maximum spring displacementand minimum tension force throughout the extent of spring displacementand permitting the heating element to be positioned in close proximityto the reflective surface.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of myelectric heater with a broken-away portion at one end showing thecontrol compartment and another broken-away portion at the opposite endshowing how the reflector is attached to the rear wall of the housing.

FIG. 2 is a fragmentary perspective view of the inside of the controlcompartment of my electric heater.

FIG. 3 is an end elevation view of my electric heater taken along line33 of FIG. 1 with the housing and fan motor support member shown insection.

FIG. 4 is a fragmentary perspective view of the heating elementsuspension arrangement when the heating element is in a contractedcondition.

FIG. 5 is the same as FIG. 4 showing the heating element suspensionarrangement in its expanded condition.

FIG. 6 is a schematic diagram showing the electric circuit of myelectric heater.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings,there is illustrated in FIGS. 1 and 3 a portable electric heater,generally shown at 10 and including a case or housing 11. The housing 11is illustrated as a rectangular housing made from sheet metal andprovided with rear wall 11a, front wall 11b with a large opening, topwall 110, end walls 11d and He and bottom wall llf. Secured within theheater housing behind the front wall opening is a reflector 12 alsoformed from sheet metal. The reflector has a reflective rear wall 120,end walls 12b and 12c, top wall 12d and bottom wall 12c. An electricalresistance heating element 13, preferably of the ribbon type, issuspended inside reflector 12, so that the reflector is effective toemit radiant heat from the heating element 13 when it is energized. Theheating element in this heater embodiment consists of three segments(13a, 13b and which are connected in series circuit through switch meansto obtain varying degrees of heat as will be discussed subsequently inconnection with FIG. 6.

The heater 10 includes a control compartment 14 at the end or portion ofthe housing opposite the reflector. The control compartment is definedby sections of the housing rear wall 110, the bottom wall 11f, top wall110, front wall Ilb, the entire end wall He and. the end wall 12c of thereflector. Within the control compartment 14 is a motor 19 that operatesimpeller 27. The motor 19 and impeller 27 comprise the fan assembly 15which is secured by means of support structure 16 to the housing rearwall 110. The rotating impeller 27 draws air into the heater through aplurality of air inlet openings 20 in the housing rear wall 11a and bydirecting the air against baffle portion 17 of support structure 16 theair is forced under pressure into an open channel along the length ofthe heater from inlet openings 20 to the far end of heater. One sidewallof the channel is formed by the rear wall 12a and top wall 12d of thereflector and the other sidewall is formed by the housing rear wall 11a.The far end wall of the channel is a U-shaped support member 53 and thenear end wall is spacing web 29 of support structure 16. The air, aftersweeping the reflector rear wall 12a, passes through outlet openings 21located at the top of the reflector l2 and out through grill 22 thatprotectively covers opening 23 in the front wall 11b of the housing. Inthis manner the heater is effective to transmit heat by convection aswell as by radiation. For ease of portability, a carrying handle 24 issecured to the housing top wall 110. To provide stability of the heater,support feet 25 with cushioning tips 26 are secured at opposite ends ofthe housing bottom wall 11f.

To control the operation of the heater there is provided a switchassembly 30 located within the control compartment 14 which controls themotor 19 and the energization of the heating element. Operating knob 31attached to switch stem 27 is accessible to the user from outside theheater housing for manually adjusting the switch. In the electric heaterillustrated there are three attainable heating levels afforded by athreesegrnented heating element which may be selectively energized bythe switch means 30 as will be more fully discussed subsequently inconnection with FIG. 6. Each of the heating element segments, designated13a, 13b and 13c, are electrically connected to the switch 30 by wireleads 28. These wire leads are of minimum length between the switchterminals and the terminal connections of the heating element arecovered on the exterior with a relatively stiff insulating material. Inthis manner should any of the connections become detached, the wire willnot move sufficiently t'o contact any part of the heater that wouldpresent an electrical shock hazard to the user should he touch theheater housing.

Within the control compartment 14 there is also a thermostat and tipoverswitch assembly 32. The thermostat portion includes a temperatureresponsive bimetallic element 34 and a pair of relatively moveablecontact blades 35 and 36 separated by ceramic washers 39. The switchassembly 32 may be adjustably controlled through rotatable stem 37 .bymeans of control knob 40. The thermostat portion of the switch operatesin the normal manner to deenergize the heating element responsive toadjustable temperature limitations built into the thermostat.

For the purpose of turning the heater off for safety purposes in theevent it is accidentally tipped over, there is provided in switchassembly 32 a tipover switch portion including a pendulum 43 pivotablyattached to contact blade 36 by rivet 38. When the weight 44 attached tothe end of the pendulum opposite from the pivot end causes the pendulumto swing the contact blades are camed out of electrical contact witheach other to thus break the circuit and deenergize both the heatingelement and the fan motor.

The thermostat and tipover switch assembly 32 and the switch assembly 30are secured within control compartment 14 by appropriate attachment tomounting plate 41 which is attached by support brackets 46 and 47 to themotor and fan support member 16. Suitable indicia may be associated withboth the switch operating knob 31 and the thermostat control knob 40 toindicate their settings.

With reference to FIGS. 1-3, the means of securing the reflector 12 tothe housing 11 is shown. The opening 23 of the heater 10 is surroundedor framed by the housing front wall 11b which has an intumed flange 48.The protective grill 22 is secured to inturned flange 48 to cover theopening. The reflector 12 is not attached to the front portion of theheater case but is secured through appropriate means to the housing rearwall 11a. The housing rear wall, reflector, heating element, fan,controls, and necessary support members may be subassembled and placedinto the housing as a unit. To secure the end of the reflector adjacentthe control compartment to the rear wall 11:: of the heater, the motorand fan support member 16 is utilized. The baffle portion 17 of thesupport member 16 is spaced from the housing rear wall 11a by formingL-shaped sections 18 in the support member 16 at all four comers andfastening these L-shaped sections to rear wall 11a through insulatinggrommets 50 by means of sheet metal screws 51. The reflective rear wall12a of the reflector 12 is attached at both the top and bottom directlyto the motor and fan support member 16 as by means of sheet metal screws52. At the opposite end of the heater from the control compartment thereflector 12 is also secured to the rear wall 11a of the housing in aspaced relationship by using U-shaped support member 53. The U-shapedsupport member 53 is vertically disposed and has spaced parallel sides53a and 53b. Side 53a is attached to the rear wall 11a of the housingand side 53b is attached to the rear wall 12a of the reflector. Theattachments to the housing rear wall lla are made through insulatinggrommets 50 and screws 51 in the same manner as described previously.When the subassembly is completed it can be inserted into the housingfrom the rear and retained in its correct position within the housing byattaching the rear wall 11a to flanges 49 of the housing by means ofsheet metal screws 54, as most clearly shown in FIG. 3.

By the particular internal arrangement of the heater components a mixedair flow system is produced. With the battle portion 17 of the motor andfan support member 16 being positioned a short distance in from the airintake openings 20 at the back of the heater the movement of most of theair towards the front of the heater is blocked, thus forcing it to moveunder pressure into the air passage channel behind the reflector thatextends the length of the reflector. Once the air is in this openchannel, the only opening for the air to exhaust from the heater isthrough the air outlet openings 21 at the top of the reflector. By thisreflector assembly arrangement and air flow system the entire area ofthe reflector rear wall is swept with moving air. This afiords maximumheat transfer from the hot reflector rear wall to the surroundingatmosphere by convection.

The heating element 13, best illustrated in FIGS. 1 and 2 of thedrawings, comprises an electrical resistance heating wire or ribbon madeof suitable material suspended within the reflector 12 betweeninsulators. The insulators are preferably made of porcelain or similarinsulating material and in this heater there are two kinds, thehook-shaped type 56 and the round terminal type 57. The round terminalinsulators 57 are used for connecting the end of each of the ribbon-typeheating element segments 13a, 13b and through connectors 58 to the wireleads 28 coming from the switch assembly 30. The hook-shaped insulatorshave the heating element looped over the hook portion to providecontinuous runs of heating element across the interior of the reflector.In this heating element arrangement a plurality of nearly horizontal andparallel runs of heating element traverse the heater opening 23 andextend the length and height of reflector rear wall 12a.

For mounting the heating element 13 within the heater in a manner tomaintain the heating element 13 under constant tension, the end walls12b and 120 of the reflector 12 are provided with vertically alignedopenings 66. These openings generally conform in shape to the crosssection of the insulator body. The terminal insulators 57 are secured tothe reflector end wall such that they are not moveable relative thereto.The hook-shaped insulators 56 pass through the openings and that portionof the insulator body inside the reflector assembly is slightly smallerso that the openings will receive the insulator during assembly. Thehook-shaped insulators on the reflector end wall 12b are moveablerelative to the reflector used. The portion of the insulator on theoutside of the reflector assembly has a retaining flange 67. To keep theheating ribbon element taut at all times there is provided individualleaf springs 68 for each of the moveable insulators located in thereflector end wall 12b furthest from the control compartment 14. Theparticular configuration of these springs are best illustrated in FlGS.4 and 5 of the drawings. Leaf springs 68 have two leg portions 69a and69b and an aperture 70 through the center body portion 71 of the spring.The hook-shaped insulators 56 are prevented from passing through theapertures 70 of the springs or the openings 66 in the reflector end wall12c, as the case may be, by flange 67 of each of the insulators. One leg69a of the spring is secured to the reflector end wall 11d by tang 75abeing inserted under lanced section 760 of the reflector end wall andthe other leg 69b is attached in the same manner to the support member53 by means of tang 75b and lanced section 761: on the support member.FIG. 4 shows the springs in their compressed condition as when theheating element is not energized and is therefore in a contracted state.FIG. 5 shows the leaf springs when the heating element is energized andin its expanded state. The springs are made of suitable metal, such asstainless steel, and because of their relatively long length from thetang at one end to the tang at the other they have two importantdesirable characteristics. They afl'ord maximum displacement of thecenter body portion H to compensate for the expansion of the heatingelement and they provide for applying minimum tension force to theheating element throughout the extent of spring displacement. Thesecharacteristics are particularly important in this heater because eachspring must maintain two runs of heating element taut and these runsextend for a considerable unsupported distance across the heater opening23. It should be noted that the lower the watts-density of the heatingelement the lower its operating temperature. Watts-density is thewattage of the heating element divided by the surface area of theheating element. Since the tensile strength of a heating element dropsdrastically as its operating temperature increases, it is advantageousto use a heating element with as great a surface area as practicalthereby increasing the strength and life of the heating element. Byusing a long heating element this may be easily accomplished. However,with a long heating element there is a greater amount of thermalexpansion that must be compensated for in order to keep the heatingelement taut. Therefore, maximum spring displacement is necessary.Coupled with obtaining maximum spring displacement is the need tominimize the tension force exerted on the heating element throughout theentire cycle of expansion and contraction because too much tension forcewould detrimentally affect the life of the heating element and wouldcause the ribbon heating element to break eventually. To obtain both ofthese desirable characteristics it is necessary that each of the leafsprings be relatively long in length which in itself presents a problemof arranging the springs so that the heating element is suspended inclose proximity to the reflective rear wall 120. By my springarrangement each of the springs are horizontally parallel to each otherand aligned vertically with one leg 69a and the center body portion 71of each spring located at a point forward of the reflector rear wall 12aand the other leg 69b located at a point rearward of the wall wherebythe heating element is suspended in close proximity to the front of thereflector rear wall.

The above-described spring arrangement provides for positioning thesuspended heating element in close proximity to and traversing theentire area of the reflector rear wall 12a thus providing maximumradiant heating of the reflector rear wall 12a for any given heat energylevel. it also allows the heating element to be suspended in runs nearlyparallel to each other thereby obtaining efficient distribution of theheating element for maximum heat output. This spring arrangement alsoallows for maintaining all heating element segments taut at all timesregardless of how many of the individual heating element segments areenergized at any one time.

Moreover, by my spring arrangement I am able to use a heating elementmade of an alloy consisting of iron, chromium and aluminum.lron-chromium-aluminum heating elements are less expensive, have ahigher-electrical resistivity, and can operate at higher temperaturesthan heating elements made of nickel-chromium, which are more commonlyused in electric heaters. The main drawback of usingiron-chromium-aluminum heating elements in heaters as opposed tonickelchromium is their lower tensile strength at elevated temperaturesand greater permanent elongation characteristics. My spring arrangementadequately compensate for these heating element characteristics evenwhen long runs of unsupported heating element are involved to achieveoperation at a relatively low temperature as explained previously.

For a description of the electrical circuit of the heater and a moredetailed discussion of its operation, reference is made to FIG. 6. Itcan be seen that three heating elements 13a, 13b and 13c are selectivelyconnected through switch assembly 30 and are connected in series withthe thennostat and tipover switch assembly 32 and fan motor 19.Conductor 79 of the line input from power cord plug 45 is connected tothermostat and tipover switch assembly 32. Conductor 80 connectsthermostat and tipover switch assembly 33 to fan motor 19 and conductor86 connects fan motor l9'to heating element segment 13a through firstjunction 87. Conductor 88 connects the opposite end of heating elementsegment 13a at second junction 89 to switch assembly 30 at terminal 1.Heating element segment 13b is connected to switch assembly 30 atterminal 5 by conductor 96 from third junction 97 and conductor 98connects fourth junction 99 to terminal 3. Heating element segment 13cis connected to switch assembly 30 by conductor 100 from fifth junction106 to terminal 6 and conductor 107 connects sixth junction 108 toterminal 4. Conductor of the line input is connected to switch 30 atterminal 2. With the foregoing electrical circuit, a four positionswitch assembly may be employed and the following operation will beprovided with the power cord plug 45 inserted into a wall receptacle. Inthe off position, neither the fan motor nor any of the heating elementsegments are energized. In the low position all six terminals of switchassembly 30 are in electrical contact with each other to provide aclosed circuit with the result that the fan motor and all three heaterelement segments 13a, 13b and 13c are energized in electrical series. Inthe medium" position terminals 1, 2, 3 and 5 of switch assembly 30 arein electrical contact to provide a closed circuit resulting in the fanmotor and only heating element segments 13a and 13b being energized inelectrical series. In the high position only terminals 1 and 2 of theswitch assembly 30 are in electrical contact to provide a closed circuitand the fan motor and only heating element segment 13a are energized. itshould be noted that the thermostat and tipover switch assembly 32 isconnected in series with the above-described circuit, therefore, asafety factor and a heating level control is provided during operationof the heater. it should also be noted that by adding in series heatingelement segment 13b to heating element segment 13a and then segment 13cin series to both segments 13a and 13b, the additional length of heatingelement or added resistances reduces the amount of current passingthrough the heating element which results in the power correspondinglybeing reduced to produce the medium" and low heat levels, respectively.This is a fundamental characteristic of a series circuit.

The foregoing is a description of the preferred embodiment of theinvention, and variations may be made to the heater without departingfrom the spirit of the invention, as defined in the appended claims.

lclaim:

1. An electric heater comprising;

a. a housing having sides, a rear wall and an open front,

b. a reflector located within the housing and secured by support meansto the rear wall of the housing in spaced relationship, said reflectorhaving a reflective surface and two opposing walls projecting forwardlyfrom said surface with each of said walls having a plurality ofapertures,

c. a heating element suspended within the reflector to provide aplurality of runs, said heating element being electrically connectedthrough terminals to a power source,

insulators supporting the suspended heating element, said insulatorspassing through the apertures in the reflector walls, and

e. individual leaf springs having a center body portion and legsextending outwardly therefrom cooperating with each of the insulatorsthat receive a run of heating element electrically connected to aterminal to maintain the runs of the heating element suspended on saidinsulators taut at all times, said leaf springs being located outsidethe reflector and each having one leg secured at a point forward of thereflective surface and the other leg secured at a point rearward of thereflective surface and with said center body portion cooperating withsaid insulators whereby the heating element is positioned in closeproximity to the reflective surface.

2. The electric heater of claim 1 wherein each spring biased insulatorpassing through the reflector end walls also passes through the centerbody portion of the leaf spring.

3. The electric heater of claim 1 wherein all of the terminalconnections for the heating element are located on one of the forwardlyprojecting reflector walls.

4. The electric heater of claim 3 wherein only the insulators located inthe reflector wall opposite the wall with the terminal connections arespring biased by a leaf spring and each of said insulators pass throughthe center body portion of the leaf spring.

5. An electric heater comprising;

a. a housing having sides, a rear wall and an open front,

b. a control compartment in one portion of the housing including switchmeans for operating the heater,

c. a sheet-metal reflector located in another portion of the housing andsecured by support means to the rear wall of the housing in spacedrelationship, said reflector having a reflective surface and twoopposing walls projecting forwardly from said surface, each of saidwalls having a plurality of apertures,

a heating element suspended within the reflector to provide a pluralityof runs, said heating element being electrically connected throughterminals to said switch means, e. insulators supporting the suspendedheating element, said insulators passing through the apertures in thereflector walls, and f. individual leaf spring having a center bodyportion and legs extending outwardly therefrom cooperating with each ofthe insulators located in the reflector wall furthest from the controlcompartment that receive a run of heating element electrically connectedto a terminal to maintain the runs of the heating element suspended onsaid insulators taut at all times, said leaf springs being locatedoutside the reflector and each having one leg secured at a point forwardof the reflective surface and the other leg secured at a point rearwardof the reflective surface and with said center body portion cooperatingwith said insulators whereby the heating element is positioned in closeproximity to the reflective surface.

6. The electric heater of claim 5 wherein the leaf springs cooperatingwith the insulators located in the reflector wall furthest from thecontrol compartment are arranged horizontally parallel to each other invertical alignment.

7. The electric heater of claim 5 wherein the heating element consistsof a plurality of heating element segments electrically connected toeach other in series circuit through said switch means for selectiveenergization.

8. The electric heater of claim 5 wherein all of the terminalconnections from the heating element to the switch means are located onthe side of the reflector closest to the control compartment.

9. The electric heater of claim 8 wherein only the insulators located inthe reflector wall furthest from the control compartment are springbiased by a leaf spring and each insulator passes through the centerbody portion of the leaf spring.

10. A portable electric heater comprising;

a. a housin having sides, arear wall and an o n front, b. a controcompartment in one end of the ousmg including therein switch means foroperating the heater,

c. a sheet-metal reflector located in the end of the housing oppositethe control compartment and secured by support means to the rear wall ofthe housing in spaced relationship, said reflector having a generallyplanar reflective surface and opposing end walls projecting forwardlyfrom said reflective surface each with a plurality of spaced verticallyaligned apertures,

d. a heating element consisting of a plurality of ribbon-type heatingelement segments suspended within the reflector electrically connectedto each other in series through said switch means to obtain varyingamounts of heat by selective energization, all of Said terminalconnections being located on the wall of the reflector closest to thecontrol compartment,

e. insulator members for supporting the suspended heater element passingthrough the apertures in the reflector end walls, and

. individual leaf springs having a center body portion and legsextending outwardly therefrom, each of said leaf springs receivingthrough the center body portion thereof the insulator members passingthrough the reflector end wall furthest from the control compartment andcooperating with said insulators to maintain said heater elementsegments taut at all times, said leaf springs being located outside saidreflector and each having one leg secured at a point forward of thereflective surface and the other leg secured at a point rearward of thereflective surface whereby the insulators and heater element arepositioned forward of and in close proximity to the reflective surface.

1. An electric heater comprising; a. a housing having sides, a rear walland an open front, b. a reflector located within the housing and securedby support means to the rear wall of the housing in spaced relationship,said reflector having a reflective surface and two opposing wallsprojecting forwardly from said surface with each of said walls having aplurality of apertures, c. a heating element suspended within thereflector to provide a plurality of runs, said heating element beingelectrically connected through terminals to a power source, d.insulators supporting the suspended heating element, said insulatorspassing through the apertures in the reflector walls, and e. individualleaf springs having a center body portion and legs extending outwardlytherefrom cooperating with each of the insulators that receive a run ofheating element electrically connected to a terminal to maintain theruns of the heating element suspended on said insulators taut at alltimes, said leaf springs being located outside the reflector and eachhaving one leg secured at a point forward of the reflective surface andthe other leg secured at a point rearward of the reflective surface andwith said center body portion cooperating with said insulators wherebythe heating element is positioned in close proximity to the reflectivesurface.
 2. The electric heater of claim 1 wherein each spring biasedinsulator passing through the reflector end walls also passes throughthe Center body portion of the leaf spring.
 3. The electric heater ofclaim 1 wherein all of the terminal connections for the heating elementare located on one of the forwardly projecting reflector walls.
 4. Theelectric heater of claim 3 wherein only the insulators located in thereflector wall opposite the wall with the terminal connections arespring biased by a leaf spring and each of said insulators pass throughthe center body portion of the leaf spring.
 5. An electric heatercomprising; a. a housing having sides, a rear wall and an open front, b.a control compartment in one portion of the housing including switchmeans for operating the heater, c. a sheet-metal reflector located inanother portion of the housing and secured by support means to the rearwall of the housing in spaced relationship, said reflector having areflective surface and two opposing walls projecting forwardly from saidsurface, each of said walls having a plurality of apertures, d. aheating element suspended within the reflector to provide a plurality ofruns, said heating element being electrically connected throughterminals to said switch means, e. insulators supporting the suspendedheating element, said insulators passing through the apertures in thereflector walls, and f. individual leaf spring having a center bodyportion and legs extending outwardly therefrom cooperating with each ofthe insulators located in the reflector wall furthest from the controlcompartment that receive a run of heating element electrically connectedto a terminal to maintain the runs of the heating element suspended onsaid insulators taut at all times, said leaf springs being locatedoutside the reflector and each having one leg secured at a point forwardof the reflective surface and the other leg secured at a point rearwardof the reflective surface and with said center body portion cooperatingwith said insulators whereby the heating element is positioned in closeproximity to the reflective surface.
 6. The electric heater of claim 5wherein the leaf springs cooperating with the insulators located in thereflector wall furthest from the control compartment are arrangedhorizontally parallel to each other in vertical alignment.
 7. Theelectric heater of claim 5 wherein the heating element consists of aplurality of heating element segments electrically connected to eachother in series circuit through said switch means for selectiveenergization.
 8. The electric heater of claim 5 wherein all of theterminal connections from the heating element to the switch means arelocated on the side of the reflector closest to the control compartment.9. The electric heater of claim 8 wherein only the insulators located inthe reflector wall furthest from the control compartment are springbiased by a leaf spring and each insulator passes through the centerbody portion of the leaf spring.
 10. A portable electric heatercomprising; a. a housing having sides, a rear wall and an open front, b.a control compartment in one end of the housing including therein switchmeans for operating the heater, c. a sheet-metal reflector located inthe end of the housing opposite the control compartment and secured bysupport means to the rear wall of the housing in spaced relationship,said reflector having a generally planar reflective surface and opposingend walls projecting forwardly from said reflective surface each with aplurality of spaced vertically aligned apertures, d. a heating elementconsisting of a plurality of ribbon-type heating element segmentssuspended within the reflector electrically connected to each other inseries through said switch means to obtain varying amounts of heat byselective energization, all of said terminal connections being locatedon the wall of the reflector closest to the control compartment, e.insulator members for supporting the suspended heater element passingthrough the apertures in the reflector end walls, and f. individual leafsprings having a center body portion and legs extending outwardlytherefrom, each of said leaf springs receiving through the center bodyportion thereof the insulator members passing through the reflector endwall furthest from the control compartment and cooperating with saidinsulators to maintain said heater element segments taut at all times,said leaf springs being located outside said reflector and each havingone leg secured at a point forward of the reflective surface and theother leg secured at a point rearward of the reflective surface wherebythe insulators and heater element are positioned forward of and in closeproximity to the reflective surface.